Wire-mesh troughs are typically used to hold wires and cables in such a manner that they are solidly supported yet readily accessible. Thus it is standard to provide such troughs adjacent the ceiling in computer rooms and the like.
The typical trough is made of a plurality of relatively stiff longitudinal rods and at least two crosswise U-shaped rods to which they are welded, for instance with four longitudinal rods at the base of the U-shaped cross rod and two more longitudinal rods forming sides of the trough and secured to the up-wardly pointing arms of the cross rods. Of course angled troughs are provided for going around corners and changing levels and T- or X-shaped troughs are provided for forming intersections where several such troughs are joined together.
All these wire-mesh structures typically end at a standardized U-shaped end defined by a single cross rod and the ends of the longitudinal rods. This makes it possible to join the various structures together into any shape, achieving a relatively good custom fit.
To this end the structures to be joined are typically butted endwise and secured together with clips. As described in commonly owned U.S. patent application Ser. No. 09/159,486 a clip is used with a pair of wire troughs having a cross U-shaped end rod of predetermined diameter joined to ends of longitudinal rods. The clip is U-shaped and engaged around the end rods between a respective pair of the longitudinal rods. It has a floor engaging the two end rods and is formed with a pair of flanks each engaging a respective one of the ends rods and each formed with a respective formation retaining the respective end rod against the floor. A similar clip-connecting system is described in German patent document 690 14 509. The disadvantage of these systems is that these separate clips not only constitute a separate element that needs to be manufactured and provided with the troughs, but they can get lost or knocked loose, making it impossible to join the troughs together.
As described in German patent document 693 04416 it is also known to provide separate connector bars on the sides of the troughs that project from one end and can be slipped around the cross bars of another trough to join two such troughs together. These bars have the advantage that they are fixed on the troughs so they cannot get lost or come loose. Nonetheless they add to the manufacturing costs of the troughs and create a clear and unattractive demarcation between adjacent troughs. Furthermore at the end of the trough it is necessary to leave the clips protruding, producing an unattractive appearance, or to break them off which is an extra step and also often results in a rough broken end.